As cannabis is legalized and is more accessible in various forms across the country, there is increasing concern among health care providers about potential impact on children. Researchers at Nationwide Children's Hospital have new findings to add to the existing evidence that cannabis exposure before birth can negatively impact children.

In a study published today in JAMA Pediatrics, researchers found prenatal cannabis exposure was associated in early childhood with poorer thinking skills and behaviors such as impulse control, paying attention, planning ability, and more aggressive behavior, all of which play a vital role in how children perform in school and interact with others.

"Although cannabis is a natural product, there are still many risks to using it during pregnancy," said Sarah Keim, Ph.D., principal investigator in the Center for Biobehavioral Health at Nationwide Children's, and lead author of the study.

"Some women may turn to cannabis to help deal with some common issues of pregnancy including nausea, sleep problems and stress. This is not recommended. Consulting with a health care provider to find safer options to help with these issues during pregnancy is important."

Researchers used multiple assessments, including asking parents about their child's typical behaviors and measurement of skills related to impulse control, paying attention, solving problems, and managing emotions in preschool-aged children. Results showed children exposed to cannabis had more difficulty controlling their impulses, paying attention and planning, and showed more aggressive behavior when researchers observed their behavior in a play laboratory environment.

"Our findings were not surprising—they actually confirm and expand on longstanding evidence from previous research," said Dr. Keim. "With our more contemporary and diverse sample of women and children, and with much higher potency of cannabis now than in past decades, this study validates previous research and supports existing clinical recommendations for patients."

The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists both caution against cannabis use during pregnancy because of possible health risks to mothers and children.